Understanding Algebraic Expressions and Mathematical Proofs
When working with algebraic expressions, it's essential to understand how to manipulate and simplify them effectively. Let's explore some fundamental concepts in Aiming for Grade 7 Maths Paper problems involving factorization, expansion, and mathematical proofs.
Definition: Factorization is the process of breaking down an algebraic expression into the product of simpler expressions, while expansion involves multiplying terms to create a longer expression.
Starting with factorization, let's examine the expression 3t + 12. This can be factored by finding the greatest common factor (GCF) of all terms. Both terms share a common factor of 3, resulting in 3(t + 4). This demonstrates how factoring simplifies expressions and reveals their underlying structure.
Moving to expansion and simplification, consider the expression 7(2x + 1) + 6(x + 3). When we expand this using the distributive property, we get 14x + 7 + 6x + 18, which simplifies to 20x + 25. This can be further factored as 5(4x + 5), revealing an important property about multiples of 5.
Example: To prove that an expression is always a multiple of 5 when x is a whole number:
- Start with 7(2x + 1) + 6(x + 3)
- Expand to get 20x + 25
- Factor as 5(4x + 5)
- Since 5 is a factor, the result must be a multiple of 5